1. Field of the Invention
The present invention relates to an integrated circuit package.
2. Description of Related Art
Integrated circuits are typically housed within a package that is soldered to a printed circuit board. The integrated circuit generates heat which is typically removed from the package by an external fan. The packages are typically constructed from a ceramic or plastic material which has a relatively low thermal coefficient of conductivity. The high thermal impedance of the package produces an undesirable temperature differential between the ambient air and the junction temperatures of the integrated circuit.
Highly functional integrated circuits such as microprocessors generate a large amount of heat which must be removed while maintaining the junction temperatures of the circuit below a critical value. Some packages incorporate a heat slug which is thermally coupled to the die and exposed to the ambient. The heat slug provide a relatively low thermal impedance path from the die to the ambient to minimize the junction temperatures of the integrated circuit.
The heat transfer rate from the die is proportional to the outer surface area of the heat slug. The outer surface of the heat slug is limited by the size of the package. One approach to maintaining the junction temperature of the integrated circuit is to increase the size of the heat slug and the package. Increasing the size of the package is generally undesirable, because a larger package occupies valuable board space. To effectively cool devices which generate a large amount of heat it would be desirable to provide a package that is more thermally efficient than packages of the prior art.